So the BPI wants to stop piracy. Who'd have guessed? But the really interesting thing for me is that ISPs are getting involved, with the 'big six' signing up to the BPI's treaty – designed to make a "significant reduction" in the 3.5m Brits who apparently download illegally.

It's no wonder the BPI wants to stop illegal downloading -it's expected to cost the industry £1 million over the next half-decade, but why the ISPs?

Interesting that, in April, Carphone Warehouse (behind Talk Talk and AOL UK) said that it wouldn't be getting involved, adding that ISPs shouldn't be the "internet police."

However, another factor could have swayed its mind. Legal music downloads are growing at an exponential rate. And, while Apple leads the way, DRM-free services are becoming big business.

And, hey presto, a lot of these are backed by ISPs. Sky announced its forthcoming offering earlier this week, while MyMobileMusic.co.uk was hyped up in a Carphone press release from March.

So we could, in fact, end up with a scenario where ISPs are reducing the bandwidth of large-scale downloaders – not because of concerns over piracy, but because they want their own legal download services to succeed. After all, such a move would still be a victory for the BPI.

Of course, what people will do when they receive these letters is the subject of some debate, as is what people will do if they ignore them. ISPs won't want to bin thousands of customers, so chances are ISPs will simply work to limit bandwidth at peak times, with further sanctions if usage does not improve.

As The Times points out, the real problem will be for parents, who could find themselves restricted for their kids actions - though, I believe, every parent should keep an eye on their child's net activity.

And finally, another point of interest. My colleague Adam Hartley points out that the real winners could, in fact, be smaller ISPs who benefit in the short term from people moving providers. And I'm definitely behind any levelling of the ISP playing field.

We'll be bringing you more on this story throughout the day.